1. Field of the Invention
The present invention relates to a division of pixels of color filters used in a color liquid crystal display panel or the like. Particularly, the invention relates to the correlation between a high-definition liquid crystal panel and a low-price AV (audio-visual) liquid crystal television panel as well as to a method of manufacturing these two modules correlated to each other.
2. Description of the Related Art
Conventionally, in manufacturing both a high-definition liquid crystal display panel and a low-price AV liquid crystal television panel, TFT (thin film transistor) substrates, which have different design specifications in resolution or a number of pixels, are formed on respective glass substrates from the beginning, and then a color filter substrate, driving circuit and driving ICs are formed to match respective TFT substrates and then they are assembled together.
When a high-definition liquid crystal panel and a low-price AV liquid crystal television panel are manufactured, even if they have the same display sizes and different numbers of pixels, the conventional art does not have an idea of using a common TFT substrate by changing the color filters, driving ICs and driving circuits.
Japanese Unexamined Patent Publication JP-A 6-82617 (1994) (Applicant: FUJITSU CO. LTD.) is directed to a method of dividing pixels in pixel groups each of which is composed of a plurality of color pixels and discloses that color filters are provided which are capable of accommodating to graphics, characters and drawings, respectively. Though the Gazette discloses that a single pixel group consists of three pixels for R, G and B having different shapes respectively, it does not disclose that the scale of each pixel group is changed, namely the resolution is varied by forming one pixel group consisted of plural pixels of different colors such as R, G, B and like colors wherein the number of pixels is the product by a factor of an integer.
Alternatively, Japanese Unexamined Patent Publication JP-A 11-7269 (1999) (Applicant: SONY CO., LTD.) discloses a driving method in which pixels arranged in a matrix form over substantially the entire screen of a panel are laid out, namely a plurality of pixels are allocated to a single pixel group irrespective of the resolution of an inputted video signal in order to provide a display apparatus having ability to accommodate to a plurality of video signals having different standards by devising signal processing for a panel having fixed pixels and a fixed total number of pixels such as a liquid crystal display panel or a plasma display panel.
This Gazette, however, does not disclose that the arrangement of color filters is changed with varying respective resolution.
In the conventional process for manufacturing both a high-definition liquid crystal display panel and a low-price AV liquid crystal television panel, it is necessary to initially form TFT substrates having different design specifications in resolution or number of pixel groups, and then form color filter substrates, driving circuits and driving ICs such as to match TFT substrates respectively. Thus, member sharing of TFT substrate or the like is not performed. Neither JP-A 6-82617 nor JP-A 11-7269 discloses any art of using a TFT substrate adapted for display of high resolution video signals and a color filter substrate adapted for display of low resolution video signals which is different from a color filter substrate adapted for high resolution thereby providing a panel for display of low resolution video signals.
An object of the invention is to provide a liquid crystal display apparatus capable of being used for both high-definition liquid crystal panels and low-price liquid crystal television panels, thereby enhancing the production efficiency and yield of such panels, and a method of manufacturing the same.
The invention provides a liquid crystal display apparatus comprising a pair of substrates, a plurality of pixel electrodes which are arranged in a matrix form, formed on one substrate of the pair of substrate, and a plurality of color filters of n (n is an integer of two or more) number of colors corresponding to the plurality of pixel electrodes, the plurality of color filters being arranged so that color filters of a same color sequentially form m (m is an integer of two or more) number of columns, wherein nxc3x97mxc3x97l (l is a natural number) pixels form one pixel group.
According to the invention, since one pixel group consists of nxc3x97mxc3x97l pixels, when both a high-definition liquid crystal panel and a low-price liquid crystal television panel are manufactured, if they have the same display size but different numbers of pixels, by using a TFT substrate as a common part and using different color filter substrate, driving ICs and driving circuit, it is possible to manufacture both the high-definition liquid crystal panel and the low-price liquid crystal television panel by changing only the latter half of a production line, whereby the delivery time can be shortened. Further, since commonality of components can be achieved, the production efficiency is improved.
In the low-price liquid crystal panel, since each pixel group consists of a plurality of pixels and has an wide area, even if one of pixels is defective, such a defective pixel is difficult to be recognized visually and hence does not render the one pixel group defective. This leads to an improved production yield of liquid crystal panels, hence, to an improved efficiency in volume production.
In the case where such a defective pixel forms a black spot, such a black spot is difficult to be recognized as a defect when the size of such a pixel is approximately the same as that of a pixel for use in a high-definition panel. Even where such a defective pixel forms a bright spot, if a bright spot is modified into a black spot, it will be more hardly recognized as a defect, thus leading to a further improved production yield.
In the invention it is preferable that each of the plurality of pixel electrodes is provided with a TFT.
According to the invention, a TFT substrate can be used.
In the invention it is preferable that the n number of colors are three primary colors consisting of red (R), green (G) and blue (B).
According to the invention, it is possible to display a color image composed of the three primary colors, namely, R, G and B.
In the invention it is preferable that the color filters are formed on the other substrate of the pair of substrates.
According to the invention, the color filters can be formed on the TFT substrate or the counter substrate.
In the invention it is preferable that the liquid crystal display apparatus comprises a driver the same as that used in a liquid crystal display apparatus having color filters of n number of colors arranged sequentially, and different color filters and controller from those used in the latter liquid crystal display apparatus.
According to the invention, in a high-definition liquid crystal panel and a low-price liquid crystal panel, a common part can be used.
In the invention it is preferable that the liquid crystal display apparatus in which the nxc3x97mxc3x97l pixels form one pixel group is constructed by short-circuiting a bus line extending in the direction of column at every m pixels or a bus line extending in the direction of row at every one pixel.
According to the invention, the number of internal circuits in the horizontal and vertical drivers can be significantly reduced by short-circuiting the bus lines.
The invention provides a method of manufacturing a liquid crystal display apparatus comprising a step of laminating a TFT substrate on which a plurality of pixel electrodes are arranged in a matrix form, and a color filter substrate on which a plurality of color filters of n (n is an integer of two or more) number of colors corresponding to the plurality of pixel electrodes, the plurality of color filters being arranged so that color filters of a same color sequentially form m (m is an integer of two or more) number of columns, to form one pixel group consisting of nxc3x97mxc3x97l (l is a natural number) pixels.
According to the invention, since one pixel group consists of nxc3x97mxc3x97l pixels, when both a high-definition liquid crystal panel and a low-price liquid crystal television panel are manufactured, if they have the same display size but different numbers of pixels, by using a TFT substrate as a common part and using different color filter substrate, driving ICs and driving circuit, it is possible to manufacture both the high-definition liquid crystal panel and the low-price liquid crystal television panel by changing only the latter half of a production line, whereby the delivery time can be shortened. Further, since commonality of components can be achieved, the production efficiency is improved. In the low-price liquid crystal panel, since each pixel group consists of a plurality of pixels, even if one of pixels is defective, such a defective pixel does not render the one pixel group defective. This leads to an improved production yield of liquid crystal panels.